Cable television systems generate different types of messages that are distributed from a headend to one or more set top boxes via a cable television network. These messages include general messages that are broadcast to multiple set top boxes as well as targeted messages that are addressed to a particular set top box. Targeted messages may include, for example, billing information, new account information, and security settings. Targeted messages are bandwidth intensive because they are sent exclusively to each set top box. These targeted messages are necessary for messages containing private information.
Problems may occur when messages are sent to set top boxes that are offline due to a power failure, a network failure, or the like. For example, a large number of targeted messages sent to offline set top boxes consumes network bandwidth without actually delivering the targeted messages to the appropriate set top boxes. These undelivered messages will need to be re-sent at a future time, which consumes additional network bandwidth.
Additionally, the number of outstanding (i.e., unacknowledged) targeted messages are typically limited by the cable television system. When the maximum number of outstanding targeted messages is reached, additional targeted messages cannot be distributed until one or more of the outstanding targeted messages is acknowledged or reaches a time-out value and is designated as undelivered. Thus, sending too many targeted messages to offline set top boxes can significantly increase the time to distribute a group of targeted messages. For example, waiting for time-outs to occur before resending subsequent messages reduces the overall message throughput.
Therefore, it would be desirable to provide a system that prioritizes targeted messages based on knowledge of offline set top boxes in different parts of the cable television network as well as the integrity of different portions of the network.